What causes fatigue and muscle pain? 44 possible conditions

See a list of possible causes in order from the most common to the least.

Chronic fatigue syndrome (CFS) is a debilitating disorder characterized by intense fatigue that cannot be cured with sleep. Mental and physical activities may cause symptoms to worsen. When fatigue cannot be linked to ...

Common colds and influenza are contagious infections that affect the respiratory system. Both are airborne illnesses, spread through coughing and sneezing. Shared symptoms include headache, cough, sore throat, and more.

This condition is considered a medical emergency. Urgent care may be required.

Also known as hypoglycemia, low blood sugar can be a dangerous condition. Hypoglycemia is rare in people who are not suffering from diabetes, the chronic disease that affects the body's ability to regulate blood sugar...

Rheumatoid arthritis (RA) is an autoimmune disease, a disease in which the immune system mistakes the body's own cells for invaders. In RA, the immune system attacks the synovia, the membranes lining the joints.

Hepatitis is swelling and inflammation of the liver. It's usually caused by a viral infection. There are several types of hepatitis, including: A, B, C, D, and E. Symptoms may not occur until liver damage occurs.

Polymyalgia rheumatica is an inflammatory disorder that causes pain and stiffness in various parts of the body, including the shoulders, neck, arms, thighs, and hips. The cause of this disorder is unknown.

The thyroid gland produces a hormone that controls how your cells use energy (metabolize). Hypothyroidism occurs when the body doesn't produce enough. Untreated, it can cause comlications like obesity and heart disease.

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